Agent Name

Hydrogen iodide

Alternative Name

Hydriodic acid

CAS Number

10034-85-2

Formula

H-I

Major Category

Toxic Gases & Vapors

Synonyms

Acide iodhydrique [French]; Acido yodhidrico [Spanish]; Anhydrous hydriodic acid; Hydriodic acid, solution; Hydrogen iodide solution; Hydrogen iodide, anhydrous; Hyriodic acid; Iodure d'hydrogene anhydre [French]; Yoduro de hidrogeno anhidro [Spanish]; [ChemIDplus] UN2197; UN1787 (solution)

Category

Acids, Inorganic

Description

Colorless acrid gas that fumes in moist air; Hydriodic acid: Colorless liquid that quickly turns yellowish or brown on exposure to light and air; [Merck Index] Colorless compressed liquefied gas with a pungent odor; [ICSC]

Sources/Uses

Used as a reducing agent and in laboratory analysis; Used to produce pharmaceuticals, disinfectants, and other chemicals; [HSDB]

Comments

Highly corrosive to skin; [Quick CPC] Inhalation exposures of 35 ppm can cause irritation of the throat, and higher exposures can cause laryngeal edema and pulmonary edema. [HSDB] When spilled in water, Acetyl iodide can release Hydrogen iodide. [ERG 2012] Decomposed by light; Anhydrous hydrogen iodide forms hydriodic acid when mixed with water; A strong irritant; [Merck Index] Evaporating liquid can cause frostbite; Corrosive to skin, eye, and respiratory tract; Inhalation may cause severe swelling of the throat and pulmonary edema; [ICSC]

Exposure Assessment
TIH

Yes

TLV (ACGIH)

0.01 ppm, inhalable fraction and vapor (iodides)

Vapor Pressure

5940 mm Hg

Explanatory Notes

The Guide from the Emergency Response Guidebook is for "Hydrogen iodide, anhydrous."

Adverse Effects
Toxic Pneumonitis

Yes

Dermatotoxin

Skin Burns

Links to Other NLM Databases
Health Studies

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Toxicity Information

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Chemical Information

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Related Information in HazMap
Diseases

Occupational diseases associated with exposure to this agent: